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3 years ago

If A, B, and C are the vertices of a triangle, find AB + BC + CA.

Mathematics

1 answer:

iVinArrow [24]3 years ago

5 0

Answer:

Step-by-step explanation:

When drawing a triangle, note that the vectors can be drawn either in a clockwise or anticlockwise direction. For a triangle with vertices A, B and C, te vectors are AB, BC and CA

In vector notation CA = - AC (length CA is equal to AC but acting in opposite direction to AC)

and AB+BC = AC

To evaluate AB + BC + CA, we will substitute the vector expression above into the given expression and simplify as shown;

= (AB + BC) + CA

= AC + (-AC)

open the parenthesis

= AC-AC

= 0

<em>Hence the sum of the vector expression AB + BC + CA is a zero vector</em>

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VikaD [51]

Answer:

57 children

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Step-by-step explanation:

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Then we know that:

$x + z = 111$

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We want to find the value of x and z. Then we solve the system of equations:

-Multiplay the first equation by -4 and add it to the second equation:

$-4x - 4z = -444$

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$-0.75x = -42.75$

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alina1380 [7]

Answer:

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Step-by-step explanation:

Given that y varies directly with x it means changing x will also cause change in y

Mathematically it can be written as:

y∝x

Removing the proportionality symbol

y = kx

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Putting x=-4

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Alex787 [66]

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